IC-NRLF 


SB    70 


Growth  as  Related  to  Specific 
Gravity  ana  Size  or  Seed 


Mary  E.  Renich 


Reprinted  from  Transactions  of  the  Illinois  State  Academy 
of  Science,  Vol.  14,  1921. 


Growth  as  Related  to  Specific 

r**        »i  T  C'*          r  cv  ,  - 1 

Gravity  and  ottzfe  01  oeed 


BY 


MARY  EMMA  RENICH 
•  i 

A.  B.  University  of  Illinois,   1911 
A.  M.  University  of  Illinois,  1912 

THESIS 

Submitted  in  Partial  Fulfillment  of  the  Requirements  for  the 

Degree  of 

DOCTOR  OF  PHILOSOPHY 

IN  BOTANY 


IN 


THE  GRADUATE  SCHOOL 


OF  THE 


UNIVERSITY  OF  ILLINOIS 


1920 

Reprinted  from   the   Transactions  of  the   Illinois  State 
Academy  of  Science,  Vol.  14,  Pages  109-139. 


7 


J/f/a 


GROWTH  AS  RELATED  TO  SPECIFIC  GRAVITY 
AND  SIZE  OF  SEED* 

MARY  E.  RENICH 

TABLE  OF  CONTENTS 

Page 

I.     Introduction 1 

II.     Materials   and   Methods :    4 

1.  Selection  and  Separation  of  Seed  Used 4 

2.  Treatment  of  Seedlings    5 

III.     Discussion :     7. 

1.  Relation  of  Growth  to  Specific  Gravity  of  Seeds  at  25°  C 8 

a.  Water    Culture    8 

b.  Soil    Culture , 11 

2.  Relation  of  Growth  to  Size  of  Seed  at  25°  C 14 

3.  Temperature  in  Relation  to  Specific  Gravity  and  Size 

of    Seed    16 

4.  Some  Comparisons  of  Seedlings  in  Water  and  Soil 18 

5.  Equation  of  Growth 18 

6.  Correlation  of  Weight  and  Position  of  Cotyledons ..18 

7.  Quintile    Distributions 19 

IV.     Summary 22 

V.     Bibliography .24 

VI.     Tables 25 

VII.     Plates 3,  20 


I.      INTRODUCTION 

The  influence  of  the  size  and  of  the  weight  of  seed  on  the 
resulting  crop  has  been  a  subject  of  investigation  for  many 
years.  The  evidence  gathered  from  the  literature  in  this 
field  seems  to  show  that  large,  heavy  seeds  give  the  best  re- 
turns. A  considerable  number  of  investigators  find  that 
their  results  are  rather  conflicting.  Deherain  et  Dupont 
(4)  maintain  that  it  is  only  when  the  difference  in  the 
weights  of  the  seeds  used  is  great,  that  there  is  a 
definite  advantage  in  favor  of  the  heavier  seed.  Meyer, 
C.  H.  (13)  says  that  the  question  of  advantage  in  the 
use  of  large  and  small  seeds  as  associated  with  yields  is 
inconclusive.  Leighty,  C.  E.  (11)  condemns  the  method  of 
selecting  the  largest  seed  without  consideration  of  the  char- 
acter of  the  mother  plant;  and  Love,  H.  H.  (12)  concludes 
from  his  results  that  the  heavy  grains  of  wheat  and  oats 
come  from  the  tallest  and  heaviest  yielding  plants.  Johann- 
sen,  W.  (9)  in  his  work  on  inheritance  of  weight  shows 
that,  in  a  population  of  beans,  the  heaviest  daughter-beans 


"This  paper  is  the  thesis,  somewhat  condensed  by  the  omission  of  several 
tables,  submitted  by  the  author  in  partial  fulfillment  of  the  requirements  for 
the  degree  of  Doctor  of  Philosophy. 


49185 


are  the  progeny  of  the  heaviest  mother  beans,  but  that  in  a 
pure  line  this  is  not  necessarily  true.  DeVries  (5),  on  the 
other  hand,  thinks  that  the  size  and  the  weight  of  seed  are 
primarily  the  result  of  nutrition,  in  the  broad  sense,  rather 
than  the  result  of  inheritance. 

In  so  far  as  specific  gravity  is  concerned,  another  series 
of  experiments  has  been  carried  on.  Haberlandt,  F.  (6) 
found  in  working  with  wheat,  oats,  etc.,  that  the  denser 
grains  yielded  the  heavier  returns  in  grain,  and  that  the 
less  dense  ones  yielded  .the  greater  amount  of  straw. 
According  to  Wollny,  E.  (17)  the  absolute  weight  and  not 
the  specific  gravity  is  the  only  true  index  of  the  value  of  the 
grain.  Clark,  V.  A.  (2)  found  that,  except  in  the  case  of 
oil  bearing  seeds,  the  larger  number  of  good  seeds  is  near 
the  upper  limit  of  the  specific  gravity  for  the  variety.  He 
concludes,  however,  that  specific  gravity  is  of  less  import- 
ance than  size  in  seed  selection. 

While  each  of  these  fields  has  been  investigated  by  many 
workers,  a  few  have  considered  the  combined  effect  of  size 
and  of  specific  gravity  in  seed  collection.  Among  the  latter 
is  Sanborn  (16).  He  sorted  wheat  according  to  size  and 
then  separated  the  large  grain  into  two  groups  by  the  use  of 
a  brine  solution.  The  yield  from  his  lighter  grain  surpassed 
that  from  his  heavy  grain.  Degrully,  L.  (3)  in  working 
with  corn,  discarded  all  the  very  small  and  poorly  formed 
grains.  He  then  separated  out  the  lightest  one  fourth  by 
means  of  a  sodium  nitrate  solution.  He  states  that  the  dif- 
ference of  the  results  in  favor  of  the  heavy  grain  was 
remarkable. 

Practically  all  experiments  have  been  carried  on  under 
field  conditions.  They  have  had  for  their  chief  aim  the  in- 
fluence of  specific  gravity  and  of  size  of  seed  on  crop  pro- 
duction. A  few  tests  have  been  made  by  Kiesselbach  and 
Helm  (10)  to  find  the  relation  of  the  "sprout  value"  to  the 
yield  of  small  grain  crops.  The  term  "sprout  value"  is  de- 
fined by  the  authors  as,  "The  moisture-free  weight  of  the 
maximum  plant  growth  derived  from  the  seed  when 
planted  and  grown  in  a  non-nutritive  quartz  medium  and 
in  absolute  darkness/' 


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The  problem  of  finding  how  much  growth,  due  solely  to 
the  reserve  food  in  the  seed,  will  take  place  in  seedlings  from 
seeds  separated  according  to  specific  gravity  and  to  size  has 
not,  as  yet,  been  studied.  The  solution  of  this  problem  is 
the  object  of  the  experiments  here  recorded. 

II.      MATERIALS  AND  METHDOS 

(1)  Selection  and  Separation  of  the  Seed  Used. 
The  common  garden  bean  because  of  its  ready  adapt- 
ability to  laboratory  conditions  was  chosen  for  these  ex- 
periments. In  the  spring  of  1919,  ten  pounds  of  Burpee's 
Red  Valentine  seed  of  the  season  of  1918  were  divided  ac- 
cording to  their  specific  gravity  into  six  groups.  This 
separation  was  made  by  means  of  solutions  of  chemically 
pure  sodium  nitrate  dissolved  in  distilled  water.  A  prelimi- 
nary test  showed  that  few  seed  sank  in  a  solution  of  1.32 
specific  gravity,  or  floated  in  one  of  1.12.  The  solutions 
used  consequently  range  from  1.32  to  1.12  specific  gravity. 
They  were  prepared  with  the  use  of  a  Twaddell  hydrometer, 
corrected  for  60°  F.,  and  both  seeds  and  solutions  were  kept 
at  this  temperature  while  testing.  The  solutions  made  up 
differed  from  each  other  in  specific  gravity  by  .05  and,  in 
use,  were  not  allowed  to  vary  by  more  than  .005. 

A  few  seeds  were  placed  in  a  small  tea  strainer,  dipped 
into  95%  alcohol  to  remove  the  air  film  and  then  transferred 
to  a  larger  strainer  immersed  in  a  solution  of  sodium  nitrate 
of  1.32  specific  gravity.  The  seeds  which  floated  were  re- 
moved by  a  second  small  strainer  and  they  as  well  as  the 
ones  which  sank  were  rapidly  and  thoroughly  washed,  and 
spread  out  on  towels  in  a  warm  room  to  dry.  The  ones 
which  sank,  after  drying,  were  stored  in  glass  jars  for 
future  use.  After  all  the  seeds  had  been  passed  through 
the  solution  of  greatest  density  (1.32  sp.  gr.),  those 
which  floated  were  taken  in  a  similar  manner  through  the 
solution  next  lower,  solution  of  1.27  sp.  gr.,  etc.  By  this 
method  six  groups  of  seeds  were  obtained.  These  groups 
are  designated  in  the  discussion  and  in  the  tables  as  follows : 

Density  1,  seeds  which  sank  in  a  solution  of  1.32  sp.  gr. ; 

Density  2,  seeds  which  sank  in  a  solution  of  1.27  sp.  gr. ; 
(range  from  1.32-through  1.27) ; 


Density  3,  seeds  which  sank  in  a  solution  of  1.22  sp.  gr. ; 
(range  from  1.27-through  1.22)  ; 

Density  4,  seeds  which  sank  in  a  solution  of  1.17  sp.  gr.; 
(range  from  1.22-through  1.17)  ; 

Density  5,  seeds  which  sank  in  a  solution  of  1.12  sp.  gr. ; 
(range  from  1.17-through  1.12)  ; 

Density  6,  seeds  which  floated  in  a  solution  of  1.12  sp.  gr. 
By  this  method  the  seeds  were  exposed  to  the  solution  but  a 
few  seconds  and,  as  germination  and  growth  tests  showed, 
suffered  no  harm  from  the  process. 

The  seeds  passed  through  the  successive  solutions  varied 
in  length  from  8.3  mm.  to  18.5  mm.  These  were  divided  into 
three  groups  of  the  following  respective  lengths : 

Large  seeds,  range  in  millimeters  from  18.5  to  15.1; 
medium  seeds,  range  in  millimeters  from  15.1  to  11.7;  small 
seeds,  range  in  millimeters  from  11.7  to  8.3. 

(2)     Treatment  of  Seedlings. 

Twenty-four  seeds  of  each  group  were  individually 
weighed  and  measured.  Twelve  were  placed  in  beakers  of 
sphagnum,  the  others  were  planted,  one  quarter  of  an  inch 
below  the  surface  of  the  soil,  in  small  flower  pots.  In  put- 
ting the  seeds  to  germinate,  the  micropyle  end  was  always 
placed  down  thereby  avoiding  unnecessary  curving  of  the 
seedling.  The  beakers  and  the  pots  were  kept  in  covered 
metal  cases  at  a  temperature  of  20 °C  during  germination. 
When  the  seedlings  in  the  sphagnum  started  to  put  forth 
secondary  roots  they  were  transferred  to  small  aspirator 
bottles  filled  with  tap  water.  This  water  is  essentially  a 
nutrient  solution  as  the  chemical  analysis  given  by  the  Illi- 
nois State  Water  Survey  (8)  shows.  The  seedlings  were 
held  in  place  by  means  of  fine  aluminum  wire  and  by  a  sup- 
port which  was  fastened  to  the  neck  of  the  bottle.  The  bot- 
tles were  then  placed  into  the  cases  where  they  were  left 
until  the  seedlings  were  ready  for  use.  The  water  in  the 
bottles  was  renewed  on  alternate  days. 

When  the  seedlings  were  one  or  two  centimeters  in 
height,  the  pots  or  bottles  were  placed  into  rectangular 
metal  cases  consisting  of  a  lower  part  fifteen  centimeters  in 


height  and  a  tall  upper  part  which  fits  down  over  the  former 
leaving  an  air  space  of  one  centimeter  between  the  lower 
and  upper  parts.  By  this  means  all  light  was  excluded  but 
air  exchange  was  not  prevented.  These  small  cases  were 
placed  in  special  large  constant  temperature  cases  designed 
by  Professor  Charles  F.  Hottes.  The  seedlings  were  re- 
moved from  the  cases  daily,  measured  and  watered.  Dur- 
ing the  period  of  measuring,  approximately  ten  minutes, 
the  seedlings  were  exposed  to  the  light  and  to  the  temper- 
ature (20° C)  of  the  laboratory.  Seedlings  deformed  or 
otherwise  abnormal  were  discarded.  They  were  grown  in 
series  at  temperatures  20°,  25°  and  30 °C.  The  large  seeds, 
of  which  only  a  very  limited  number  were  on  hand,  were 
grown  at  25 °C  only. 

All  measurements  were  taken  beginning  two  and  one- 
half  centimeters  above  the  root  origin.  If  the  entire  height 
of  the  shoot  is  desired,  two  and  one-half  centimeters  must 
be  added  to  the  total  height  of  the  shoot  as  recorded  in  the 
tables.  In  those  cases  in  which  the  cotyledons  were  not 
opposite,  the  length  of  the  hypocotyl  was  measured  to  the 
insertion  of  the  lower  cotyledon.  The  length  of  the  inter- 
nodes  were  taken  from  the  lower  part  of  one  node  to  the 
lower  part  of  the  next  higher  or,  in  the  case  of  the  upper 
internode,  to  the  growing  point.  A  centimeter  rule  was 
used  and  the  measurements  were  read  to  the  nearest  milli- 
meter. From  the  record  of  these  daily  measurements,  the 
daily  growth  increments  given  in  the  tables  were  obtained. 

When  a  shoot  showed  no  growth  since  the  previous  day 
its  diameter,  one  centimeter  below  the  insertion  of  the  coty- 
ledons, was  taken  by  means  of  a  vernier  callipers.  The 
seedling  was  then  removed  from  the  soil  or  the  water,  the 
root  was  washed,  superficially  dried,  and  separated  from 
the  shoot.  Then  the  fresh  weights  of  root  and  shoot  were 
obtained.  These  parts  were  dried  to  constant  weight  in  an 
electric  oven.  All  weights  were  read  to  the  fourth  decimal 
place. 

The  data  for  the  several  series  are  given  in  *  Tables  1  to 
47.  Data  are  given  for  individual  seedlings  grown  at  the 
temperature  25°C;  for  those  grown  at  20°  and  30°C,  the 


data  given  consists  of  averages,  taken  in  most  cases  from 
eight  seedlings.  In  a  few  cases,  where  germination  was 
poor,  or  seedlings  were  discarded  because  of  abnormality 
or  accident,  the  averages  include  a  smaller  number.  Meas- 
urements of  seedlings  were  taken  to  tenths  of  centimeters, 
but  the  calculation  of  averages  was  made  to  the  third  deci- 
mal place  and  are  recorded  to  the  second. 

III.     DISCUSSION 

Daily  observation  of  the  seedlings  made  evident  a  strik- 
ing correlation  between  the  amount  and  rate  of  growth  and 
the  specific  gravity  and  size  of  the  seed.  So  marked  and 
regular  is  the  correlation  that  it  was  possible,  as  a  rule,  to 
select  the  seedlings  from  seeds  of  certain  densities  and  sizes 
by  their  general  appearance.  This  was  especially  true  for 
the  seedlings  from  seeds  of  Densities  2  and  3,  for  these  ap- 
peared more  uniform  in  size  and  consequently  in  the  rate 
of  growth.  They  were  also  more  sturdy  and  of  a  deeper 
yellow  color  than  those  from  seeds  of  the  lower  densities. 
Now  and  then  a  group  from  Density  4  would  be  mistaken  for 
those  of  the  higher  densities.  This  is  apparently  in  agree- 
ment with  the  results  that  Degrully  (3)  obtained  in  his 
work  with  wheat.  He  found  that  the  plants  from  the  den- 
ser grains  were  greener,  more  vigorous,  and,  during  their 
early  growth,  showed  a  great  superiority  over  those  from 
the  less  dense  grains.  Because  of  heavy  rains,  his  plants  of 
both  groups  suffered  greatly  from  rust  and  he  was  unable 
to  make  comparisons  of  the  final  growth.  A  study  of  the 
data  as  recorded  in  the  tables  shows  that  the  differences 
noted  in  the  seedlings  are  not  differences  of  appearance 
only. 

Because  seedlings  from  seeds  of  all  sizes  and  densities 
were  grown  at  25° C  the  Tables  1  to  17  and  21  to  36  have 
the  data  given  for  individual  seedlings.  A  comparison  of 
individuals  is  not  undertaken  because  that  would  lead  to 
a  study  of  individual  variation.  In  order  to  show  the  su- 
periority of  some  groups  over  others,  the  groups  will  be 
compared  in  respect  to  their  average,  maximum  and  mini- 
mum values.  Because  of  differences  between  the  seedlings 
grown  in  water  and  those  grown  in  soil  each  culture  will  be 
studied  separately. 


1.    Relation  of  Growth  to  Specific  Gravity 

of  Seeds  at  25°  C. 
a.     Water  Culture. 

Size. — A  comparison  of  average  values  for  the  seedlings 
grown  in  water,  at  temperature  25 °C  can  be  most  readily 
obtained  by  a  study  of  Tables  18  to  20 ;  for  the  maximum 
and  minimum  values,  *  Tables  1  to  17. 

An  examination  of  the  average  values  for  the  heights  of 
the  shoots  shows  that  the  greatest  and  second  greatest  aver- 
age heights  of  seedlings  from  seeds  of  each  of  the  three 
size  groups  are  for  seedlings  from  seeds  of  Density  1,  2  or 
3.  These  average  heights  are  graphically  shown  in  Plate 
I.  In  the  hypocotyl  and  first  internode  no  correlation  be- 
tween average  length  and  specific  gravity  of  seed  is  ap- 
parent, but  a  direct  relation  does  exist  between  these  fac- 
tors in  the  second  and  third  internodes,  in  that,  the  lower 
the  density  of  the  seed,  the  shorter  the  internodes.  Fourth 
internodes  developed  only  in  seedlings  from  seeds  of  Den- 
sities 1  and  3.  There  is  also  a  direct  relation  between  aver- 
age diameter  of  seedlings  and  specific  gravity  of  the  seeds ; 
the  seedlings  from  the  denser  seeds  are  larger  in  average 
diameter  than  those  from  the  less  dense. 

In  studying  the  maximum  and  minimum  values  of  seed- 
lings from  seeds  of  the  several  densities,  *  Tables  1  to  17 
are  used.  For  the  small  seeds,  the  greatest  shoot  height  is 
that  of  a  seedling  from  a  seed  of  Density  5.  The  second 
in  height  is  from  a  seed  of  Density  3.  For  the  medium 
seeds,  the  three  tallest  seedlings  of  the  series  are  from  seeds 
of  Density  3.  The  two  tallest  seedlings  from  the  large  seeds 
are  of  seeds  of  Density  2,  the  third  tallest,  from  a  seed  of 
Density  3. 

As  in  the  case  of  the  average  length  of  hypocotyls  and 
first  internodes  so  here,  there  exists  no  definite  relation 
between  maximum  lengths  of  seedlings  of  the  different 
groups  and  specific  gravity  of  seed.  In  the  second  and  third 
internodes,  the  maximum  lengths  for  the  several  series  are 
in  every  case,  in  seedlings  from  seeds  of  one  of  the  three 
highest  densities.  There  is  a  marked  difference  between 
the  maximum  lengths  of  these  internodes  in  the  seedlings 


from  seeds  of  the  higher  and  lower  densities.  While  in 
average  values,  the  diameter  of  the  shoot  varied  with  the 
density,  this  does  not  hold  true  for  the  maximum  values. 

With  but  few  exceptions  the  minimum  values  for  shoot 
height  and  diameter  are  found  in  seedlings  from  seeds  of 
Density  5  or  6,  usually  the  latter. 

From  these  comparisons  we  may  conclude  that,  for  seed- 
lings grown  in  water  at  a  temperature  of  25 °C. 

(1)  The  greatest  height  and  diameter  of  shoot  are 
found  in  seedlings  from  seeds  of  Densities  1,  2  and  3 ;  in 
Density  2  or  3  more  often  than  in  1; 

(2)  The  lower  the  density,  the  shorter  the  second  and 
third  internodes. 

Weight. — That  weight  is  related  to  density  is  clearly 
seen  from  a  study  of  the  tables.  The  average  weight  values 
are  considered  in  Ta~bles  18  to  20.  In  the  case  of  the  fresh 
weights  of  roots,  shoots  and  plants  for  seedlings  from  the 
large  and  the  small  seeds,  the  three  greatest  average 
weights  for  each  size  group  are  found  in  the  seedlings  of 
the  three  highest  densities.  For  the  medium  seeds,  the 
highest  average  fresh  root  weight  is  in  the  seedlings  from 
seeds  of  Density  4,  but  the  second  highest  is  in  those  of 
Density  1.  The  highest  average  values  for  fresh  shoot 
and  fresh  plant  weights  for  the  seedlings  from  these  med- 
ium seeds  are  in  those  of  the  three  highest  densities  as  was 
the  case  for  the  seedlings  from  the  small  and  large  seeds. 

The  maximum  fresh  root  weight  for  the  small  seeds  is 
found  in  a  seedling  from  a  seed  of  Density  3 ;  for  the  med- 
ium seeds  from  a  seed  of  Density  4 ;  and  for,  the  large  seeds, 
from  a  seed  of  Density  2.  The  maximum  fresh  shoot  weight 
for  the  small  seeds  is  that  of  a  seedling  from  a  seed  of  Den- 
sity 1 ;  for  medium  seeds,  of  Density  1 ;  for  large  seeds,  of 
Density  3.  The  maximum  fresh  plant  weights  for  seedlings 
from  the  small  and  the  medium  seeds  are  for  those  from 
seeds  of  Density  1 ;  for  the  large  seeds,  for  one  from  a  seed 
of  Density  2.  The  minimum  fresh  weights  are  usually  the 
weights  for  seedlings  from  seeds  of  Density  5  or  6. 

A  better  idea  of  the  actual  amount  of  growth  can  be  ob- 
tained from  the  dry  weights  than  from  the  fresh  weights. 


10 

For  the  seedlings  from  seeds  of  each  size  group,  the  three 
highest  average  dry  weights  for  roots,  for  shoots  and  for 
plants,  are  in  the  seedlings  from  seeds  of  the  three  highest 
densities.  These  average  weights,  however,  do  not  vary 
directly  as  the  densities,  for  the  highest  value  is  sometimes 
in  seedlings  from  seeds  of  Density  3,  sometimes  in  those 
from  seeds  of  Density  1  or  2.  Plate  II  represents  the  aver- 
age dry  weights  for  the  seedlings  of  each  group. 

The  maximum  dry  root  weights  for  seedlings  from  the 
small,  the  medium  and  the  large  seeds  are  in  seedlings  from 
seeds  of  Densities  3,  1  and  2  respectively.  The  maximum 
dry  shoot  weights,  and  also  the  maximum  dry  plant 
weights  are  for  seedlings  from  seeds  of  Density  1,  for  those 
from  the  small  and  the  medium  seeds,  and  Density  2  for 
those  from  large  seeds.  The  minimum  dry  weights  are,, 
as  a  rule,  in  seedlings  from  seeds  of  Densities  5  and  6. 

From  these  facts  we  may  conclude: 

(1)  That,  with  the  exception  of  the  roots  from  the 
medium  seeds,  the  greatest  fresh  weights  are  in  seedlings 
from  seeds  of  the  three  highest  densities. 

(2)  The   greatest   dry  weights   are   also  in   seedlings 
from  seeds  of  the  three  highest  densities. 

Comparison  of  Weights. — There  is  little  correlation  be- 
tween the  relation  of  dry  to  fresh  weight  and  the  specific 
gravity  of  the  seeds.  It  is  apparent,  however,  that  in  the 
seedlings  from  seeds  of  Density  3  the  average  percentage 
which  the  dry  weights  of  root,  shoot  and  plant  is  of  the 
fresh  weights  of  the  corresponding  members  is  as  great, 
sometimes  greater,  than  that  of  any  other  density. 

The  average  percentage  which  the  dry  plant  weight  is  of 
the  seed  weight  is  always  higher  for  the  seedlings  of  seeds 
of  Density  6  than  for  those  from  seeds  of  Density  1;  in 
most  cases  it  is  also  higher  than  for  those  from  seed  of 
Density  3.  This  higher  percentage  shows  that  although 
in  size  and  weight  the  seedlings  from  the  seeds  of  Density  6 
are  inferior  to  those  of  other  densities,  the  seedlings  from 
seeds  of  Density  6  appear  to  make  the  best  use  of  the  re- 
serve food  in  the  seed. 


11 


Rate  of  Growth. — Not  only  is  the  amount  of  growth 
related  to  the  specific  gravity  of  the  seed  but  there  also 
exists  a  relation  between  the  rate  of  growth  and  the  spe- 
cific gravity  of  seed.  Considering  the  rate  of  growth  as 
shown  by  the  daily  growth  increments  we  find  that,  in  gen- 
eral, seedlings  from  seeds  of  the  higher  densities  have  a 
greater  growth  rate  than  those  from  seeds  of  the  lower 
densities.  The  greatest  average  daily  increment  for  the 
small  seeds,  5.8  cm,  was  made  on  the  second  day  after  be- 
ing placed  in  the  constant  temperature  case  by  the  seed- 
lings from  seeds  of  Density  6.  For  the  medium  seeds,  the 
greatest  average  daily  increment,  7.63  cm,  was  made  on 
the  second  day  by  seedlings  from  seed  of  Density  3;  and 
for  the  large  seeds,  an  average  daily  growth  of  6.85  cm 
was  made  on  the  third  day  by  seedlings  from  seeds  of  Den- 
sity 1.  The  maximum  daily  growth  increment  of  the  seed- 
lings from  small  seeds  is  7  cm,  made  on  the  second  day  by 
a  seedling  from  a  seed  of  Density  3 ;  the  maximum  for  the 
medium  seeds  is  9.3  cm,  made  on  the  second  day  by  a  seed- 
ling also  from  a  seed  of  Density  3.  For  the  large  seeds,  the 
maximum  increment  7.7  cm  was  made  on  the  third  day  by 
a  seedling  from  a  seed  of  Density  2.  The  average  rate 
of  growth  often  decreases  more  rapidly  in  the  seedlings 
from  seeds  of  the  lower  densities  and  although  the  total 
height  of  the  seedlings  from  these  densities  is  less  than 
that  for  those  from  the  denser  seeds,  growth  usually  con- 
tinues for  as  many  days  as  in  seedlings  from  the  seeds  of 
higher  densities. 

b.    Soil  Culture. 

The  data  for  seedlings  grown  in  soil  at  temperature  25°  G 
is  given  in  Tables  21  to  40.  Tables  *21  to  36  contain  the 
records  of  the  individual  seedlings  while  the  average  values 
are  shown  in  Tables  38  to  40.  Because  of  the  limited  num- 
ber of  large  seeds  of  Densities  1  and  6  none  were  grown 
in  soil. 

Size. — Proceeding  as  in  the  discussion  of  the  seedlings 
grown  in  water,  we  find  the  greatest  average  shoot  heights 
for  the  small,  the  medium  and  the  large  seeds  respectively, 
are  for  seedlings  from  seeds  of  Densities  1,  3  and  3.  The 
highest  shoot  from  the  small  seeds  is  that  of  a  seedling 


12 

from  seed  of  Density  4,  the  second  highest,  of  Density  1 ; 
the  two  highest  for  the  medium  seeds  are  from  seeds  of 
Density  3;  the  highest  for  the  large  seeds  is  from  Density 
2  while  the  second  highest  is  from  Density  ?>.  The  mini- 
mum value  for  each  size  group  is  in  a  seedling  from  seed 
of  the  lowest  density. 

No  correlation  exists  between  density  and  average  and 
maximum  length  of  hypocotyl  and  first  internode.  The 
lengths  of  the  second  and  third  internodes  vary  as  the 
density  of  the  seeds.  No  seedlings  grown  in  soil  developed 
a  fourth  internode.  As  to  the  diameter,  we  find  the  aver- 
age size  varies  as  the  density  of  the  seed;  the  maximum 
values  are  also  in  the  diameters  of  the  seedlings  from  seeds 
of  the  higher  densities. 

In  so  far  as  size  of  seedlings  is  concerned,  the  results 
agree  in  general  with  those  for  water  grown  seedlings, — 

(1)  The  greatest  height  and  diameter  of  shoot  is  found 
in  seedlings  from  the  seeds  of  Densities  1,  2  and  3.    More 
often  in  seedlings  from  Densities  2  or  3  than  Density  1. 

(2)  The  length  of  the  second  and  third  internodes  vary 
as  the  density  of  the  seed. 

Weight. — There  is  more  variation  in  the  fresh  weight 
of  soil-grown  seedlings  than  in  those  grown  in  water.  This 
is  especially  true  in  the  root  weight.  In  the  roots  of  seed- 
lings from  small  seeds  the  greatest  average  and  maximum 
weights  are  for  those  from  the  higher  densities  and  the 
minimum  weights  are  in  those  of  lower  densities,  but  no 
general  relation  seems  to  exist  between  fresh  root  weight 
and  specific  gravity  for  seedlings  from  the  medium  and 
large  seeds. 

In  the  fresh  shoot  weights  we  have  the  greatest  average 
weights  for  the  small,  the  medium  and  the  large  seeds  in 
those  from  seeds  of  Densities  1,  2  and  3  respectively.  The 
maximum  fresh  weight  for  each  size  group  is  in  a  seedling 
from  a  seed  of  Density  3  while  the  minimum  weights  are  in 
those  from  Densities  5  or  6,  usually  6.  In  the  fresh  plant 
weights  we  find  the  same  order  as  in  the  shoot  weights 
the  greatest  average  weights  for  small,  medium  and  large 
seeds  are  in  seedlings  from  seeds  of  Densities  1,  2  and  3 


13 

respectively;  while  the  maximum  weight  for  each  group 
is  in  a  seedling  from  a  seed  of  Density  3;  the  minimum 
weights  are  in  those  of  Density  5  or  6,  usually  6. 

In  the  dry  weights  we  find  a  definite  relation  between 
density  and  weight.  This  correlation  with  plant  weight  is 
graphically  represented  in  Plate  III.  Without  exception 
the  highest  average  and  maximum  weights  for  each  size 
group  are  in  the  seedlings  from  seeds  of  Densities  1,  2  or 
3.  This  statement  holds  true  for  dry  weights  of  root, 
shoot  and  plant.  Moreover,  the  second  highest  average 
and  maximum  weights  are  in  most  cases  also  in  seedlings 
from  seeds  of  these  higher  densities.  The  lowest  average 
and  minimum  weights  are  for  seedlings  from  seeds  of  the 
lower  densities. 

Comparison  of  Weights. — The  facts  pointed  out  for  seed- 
lings grown  in  water  with  respect  to  correlation  between 
dry  and  fresh  weights  and  specific  gravity  of  seed  hold 
true  for  those  grown  in  soil.  The  seedlings  from  seeds 
of  Density  6  appear  to  lead  in  making  the  best  use  of  their 
reserve  food  as  was  the  case  in  the  water  culture. 

Rate  of  Growth. — A  study  of  the  daily  growth  incre- 
ments also  points  to  a  superiority  of  the  seedlings  from 
the  denser  seeds.  In  the  case  of  average  daily  increments 
(Tables  37-39)  we  find  the  greatest  average  increment  for 
the  small  seeds  is  7.56  cm  on  the  third  day  for  seedlings 
from  seed  of  Density  1;  for  medium  seeds,  8.9  cm  on  the 
second  day  by  those  from  seeds  of  Density  3;  for  large 
seeds,  7.67  cm  on  the  second  day  by  those  from  seeds 
of  Density  1.  From  Tables  21-36  we  obtain  as  maximum 
daily  increments,  for  small  seeds,  8.5  cm  on  the  third  day 
by  a  seedling  from  a  seed  of  Density  1 ;  for  medium  seeds, 
10  cm  on  the  second  day  by  two  seedlings  from  the  seeds 
of  Density  5  and  one  from  those  of  Density  3 ;  for  the  large 
seeds,  10.1  cm  on  the  second  day  by  a  seedling  from  seed 
of  Density  1. 

Summing  up  the  results  from  the  data  for  seedlings 
grown  in  water  and  in  soil  at  25  °C  we  find  the  following 
relations  exist  between  specific  gravity  and  growth : 


14 

(1)  The  greatest  height  and  diameter  of  shoot  are 
found  in  the  seedlings  grown  from  seeds  of  the  three  high- 
est densities; 

(2)  The  higher  the  density  of  the  seed,  the  longer  the 
second  and  third  internodes ; 

(3)  As  a  rule,  the  seedlings  from  the  denser  seeds  have 
the  highest  fresh  weight ; 

(4)  The  greatest  dry  weight  is  always  found  in  seed- 
lings from  seeds  of  the  three  highest  densities; 

(5)  The  seedlings  from  the  higher  densities  show,  on 
the  whole,  a  greater  rate  of  growth  than  do  those  from 
seeds  of  the  lower  densities. 

2.     Relation  of  Growth  to  Size  of  Seed,  at  25° C. 

Size. — That  a  definite  relation  exists  between  size  of 
seed  and  amount  and  rate  of  growth  is  shown  beyond  a 
doubt  by  the  results  of  these  experiments.  For  both  water 
and  soil  cultures  the  seedlings  from  small  seeds  are  smaller 
than  those  from  medium  and  large  seeds  in  height  and 
in  diameter  of  shoot.  This  fact  in  regard  to  shoot  height 
is  clearly  shown  in  Plates  I  and  III.  From  these  plates  we 
see  that  the  seedlings  from  small  seeds  are  not  only  shorter 
than  those  from  medium  seeds  of  the  same  density  but  the 
seedlings  from  the  small  seeds  of  the  highest  density  are 
shorter  than  those  from  the  medium  seeds  of  the  lowest 
densities.  Both  the  numerical  data  and  these  plates  show 
that  there  is  less  difference  in  height  between  the  seed- 
lings from  medium  and  large  seeds  than  there  is  between 
those  from  medium  and  small  seeds.  The  average  heights 
for  seedlings  from  the  medium  seeds  from  Densities  3  and 
5  (Table  19)  are  greater  than  those  from  the  large  seeds 
(Table  20)  of  the  same  densities.  The  maximum  heights 
for  seedlings  of  Densities  1,  3  and  5  are  also  greater  than 
the  maximum  heights  for  the  large  seeds  of  the  same  den- 
sities. 

There  is  a  greater  difference  between  the  diameters  of 
the  seedlings  from  small  and  medium  seeds  than  between 
those  from  medium  and  large  seeds.  The  lengths,  both 
average  and  maximum,  of  the  hypocotyls  in  seedlings  irom 


15 

the  medium  seeds  are  greater  than  those  of  the  small  or 
large  seeds.  There  is  little  difference  in  the  case  of  soil 
grown  seedlings  in  the  hypocotyl  lengths  of  seedlings  from 
small  and  large  seeds.  There  is  less  difference  between  the 
length  of  the  second  and  third  internodes  of  seedlings  from 
medium  and  large  seeds  than  between  those  from  medium 
and  small  of  the  same  density. 

Weight. — From  the  data  given  for  fresh  root  weight 
(Tables  18  to  20)  for  water  culture,  we  find  that  the  aver- 
age weight  for  seedlings  from  the  small  seeds  of  Density 

3  is  greater  than  that  of  those  from  the  medium  or  large 
seeds  of  like  density.     The  average  weight  for  seedlings 
from  small  seeds  of  Density  2  is  greater  than  that  of  those 
from  the  medium  seeds  of  this  density.    Again,  the  aver- 
age weight  for  seedlings  from  medium  seeds  of  Densities 

4  and  5  is  greater  than  that  of  those  from  large  seeds  of 
these  respective  densities.     The  fresh  weights  for  shoots 
and  plants  vary,  for  equal  densities,  as  the  size  of  the  seeds. 

The  dry  weights  for  seedlings  grown  in  water  also  show 
a  relation  to  size  of  seed.  In  the  roots  of  seedlings,  those 
from  the  small  seeds  of  Density  3  nearly  equal  in  average, 
minimum  and  maximum  dry  weights  the  roots  from  med- 
ium seeds  of  equal  density.  As  between  medium  and  large 
seeds,  seedlings  from  medium  seeds  of  Density  4  surpass 
those  from  the  large  seeds  in  minimum  and  average 
weight ;  and  seedlings  from  medium  seeds  of  Density  5  sur- 
pass those  from  large  seeds  in  average  and  maximum  dry 
root  weight.  In  general,  however,  the  weights  of  seedlings 
grown  in  water  from  seeds  of  equal  densities  vary  as  the 
size  of  the  seed.  The  comparison  of  average  dry  plant 
weight  is  given  graphically  in  Plate  II. 

Turning  now  to  the  data  for  average  values  in  soil  grown 
seedlings  (Tables  37  to  39)  we  find  that,  except  for  the 
average  weights  of  seedlings  from  medium  seeds  of  Density 
2,  all  average  fresh  weights  vary  as  the  size  of  the  seeds 
provided  they  are  equal  in  density.  In  the  exception  just 
cited  the  average  weights  for  seedlings  from  medium  seeds 
is  greater  than  that  for  those  of  the  larger  seed  in  the  case 
of  root,  shoot  and  plant  weights.  With  but  one  exception, 


16 

again  in  Density  2,  all  dry  root,  shoot  and  plant  weights 
vary  as  the  size  of  the  seeds  provided  we  compare  seed- 
lings from  seeds  of  the  same  density.  Plate  IV  represents 
the  average  dry  plant  weights  for  soil  grown  seedlings. 

Comparison  of  Weights. — In  general,  the  percentage 
which  the  dry  weight  of  shoot  and  plant  is  of  the  fresh 
weight  of  like  member  is  greater  for  seedlings  from  the 
large  seeds  than  from  the  medium  or  the  small  seeds.  The 
percentage  which  the  dry  plant  weight  is  of  the  seed  weight 
is  also  higher  for  seedlings  from  the  large  seeds  than  from 
the  medium  or  small  seeds. 

Rate  of  Growth. — That  the  rate  of  growth  is  also  influ- 
enced by  the  size  of  the  seed  is  shown  by  the  daily  growth 
increments.  For  water  culture  seedlings  the  average  daily 
increments  (Tables  18  to  20)  on  the  second  and  third  day 
are  greater  for  the  seedlings  from  medium  seeds  than  for 
those  of  either  small  or  large  seeds  of  like  density.  The 
greatest  average  daily  increments,  except  in  seedlings  from 
large  seeds  of  Densities  1  and  2,  are  found  in  the  seedlings 
from  the  medium  seeds.  The  maximum  daily  increment 
occurs  on  the  second  day  in  seedlings  from  the  small  and 
the  medium  seeds  but  not  until  the  third  day  for  those  from 
the  large  seeds.  The  same  superiority  in  the  rate  of  growth 
for  seedlings  from  the  medium  seeds  grown  in  soil  is  seen 
from  Tables  37  to  39. 

In  so  far  as  amount  and  rate  of  growth  are  influenced 
by  the  size  of  the  seed,  we  find: 

(1)  The  amount  of  growth  varies  with  the  size  of  the 
seed; 

(2)  There  is  more  variation  in  amount  of  growth  be- 
tween small  and  medium  seeds  than  between  medium  and 
large  seeds; 

(3)  The  rate  of  growth  of  seedlings  from  medium  seeds 
is  greater  than  that  for  those  of  small  or  large  seeds  of 
equal  density. 

3.     Temperature  in  Relation  to  Specific  Gravity 

and  Size  of  Seed. 

It  is  not  the  intention  to  discuss  in  detail  growth  at 
20°  and  30  °C,  but  rather  to  determine  whether  conclusions 


17 


drawn  for  temperature  25°  may  be  applied  to  seedlings 
from  similar  seeds  grown  at  20°  and  30 °C  respectively. 
Because  of  the  limited  number  of  large  seeds  no  data  is 
available  save  at  25 °C.  The  discussion  will  be  confined  to 
a  consideration  of  average  values.  The  data  for  seedlings 
grown  at  20°C  are  found  in  *Tables  40  to  43,  that  for  those 
grown  at  30°C  in  Tables  44  to  47. 
a.  Growth  as  Related  to  Specific  Gravity. 

A  study  of  the  above  tables  shows  that  with  but  few  ex- 
ceptions the  conclusions  drawn  for  the  relation  of  growth 
to  the  specific  gravity  of  the  seed,  for  temperature  25° C  are 
also  true  for  temperatures  20°  and  30°C.  At  25°C  there 
was  no  correlation  evident  between  length  of  hypocotyl 
and  specific  gravity  of  seed;  at  20°,  however,  the  greatest 
average  length  of  hypocotyl  in  seedlings  grown  in  soil  ap- 
pear in  those  of  Densities  1,  2  and  3. 

At  25 °C,  the  percentage  of  the  dry  plant  weight  to  the 
seed  weight  is  higher  for  seedlings  from  seeds  of  Density 
6  than  for  those  from  seeds  of  Densities  1  and  2.  At  20° C, 
this  is  true  only  for  seedlings  grown  in  water,  and  at  30 °C, 
it  applies  solely  to  seedlings  from  medium  seeds  grown  in 
water. 

b.     Growth  as  Related  to  Size  of  Seed. 

The  seedlings  grown  at  30  °C  show  the  same  correlation 
between  growth  and  size  of  seed  as  is  shown  by  those  grown 
at  25 °C.  For  the  seedlings  grown  at  20 °C,  however,  the 
following  points  of  difference  seem  evident: 

(1)  The  average  heights  and  average  weights  of  seed- 
lings from  small  seeds  are  more  nearly  equal  to  the  similar 
average  values   of  seedlings  from  medium  seeds  of  like 
densities,  at  20 °C  than  at  25 °C.    In  a  few  cases  the  average 
values   for  seedlings  from   small   seeds   exceed  those  for 
seedlings  from  medium  seeds. 

(2)  From  the  total  dry  weight  it  may  be  inferred  that 
at  20  °C  the  seedlings  from  small  seeds  use  their  reserve 
material  to  better  advantage  than  those  from  the  medium 
seeds. 

(3)  At  20° C,  the  greater  rate  of  growth  is  shown  by 
seedlings  from  the  small  seeds. 


18 

4.    Some  Comparisons  of  Seedlings  Grown  in 
Water  and  Soil. 

a.  Water  Content. — The  relation  of  the  dry  weights  to 
the  fresh  weights  shows  a  difference  in  the  relative  water 
content  of  seedlings  from  seeds  of  equal  size  and  density 
grown  in  water  and  soil.    The  percentage  of  the  dry  root 
weight  to  the  fresh  root  weight  is  greater  for  the  seedlings 
grown  in  soil ;  that  of  the  dry  shoot  and  plant  weights  to  the 
fresh  shoot  and  plant  weight  is  greater  for  those  grown  in 
water. 

The  stems  of  the  seedlings  grown  in  soil  were  brittle 
while  those  grown  in  water  could  be  coiled  without 
breaking. 

b.  Roots. — The  root  system  of  the  seedlings  grown  in 
soil  was  very  much  larger  than  that  of  seedlings  grown  in 
water.     In  the  majority  of  the  soil  culture  seedlings  the 
primary  root  soon  ceased  to  elongate  and  the  main  part  of 
the  root  system  consisted  of  several  long,  lateral  roots  aris- 
ing from  near  the  base  of  the  main  root.    In  the  seedlings 
grown  in  water  the  primary  root,  although  comparatively 
short,  was  the  main  part  of  the  root  system.    Several  short 
lateral  roots  developed  near  the  base  of  the  root  and  also 
lower  down  on  the  primary  root. 

5.     Equation  of  Growth. 

A  study  of  the  tables  here  recorded  shows  that  the  equa- 
tion of  growth  given  by  Blackman,  V.  H.  (1)  does  not  apply 
to  seedlings  grown  in  the  dark.  In  the  case  of  each  seed- 
ling grown  under  the  conditions  of  these  experiments  the 
final  dry  weight  is  much  less  than  the  initial  dry  weight  of 
the  seed.  This  would  mean,  if  Blackman's  equation  held 
true,  that  there  had  been  no  growth  in  these  seedlings. 

6.     Correlation  of  Weight  and  Position  of  Cotyledons. 

Harris  (6),  in  an  article  on  Interrelationships  in  Phaseo- 
lus,  states  that  the  green  and  dry  weights  of  the  primordial 
and  first  compound  leaves  of  plants  whose  cotyledons  are 
not  inserted  at  the  same  level  of  the  axis  are  less  than  those 
of  normal  plants.  No  such  correlation  exists  for  the  fresh 
and  dry  weights  of  the  seedlings  recorded  here.  Numerous 
examples  of  this  "abnormality"  as  Harris  calls  it,  occurred 


19 

but  no  account  was  taken  of  them  unless  the  difference  in 
level  was  at  least  2mm ;  in  some  exceptional  cases  it  was  as 
much  as  18mm.  That  no  such  correlation  exists  in  these 
seedlings  is  shown  by  a  comparison  of  the  root,  shoot,  and 
plant  weights  of  an  abnormal  seedling  with  the  corres- 
ponding average  weights  of  the  group  to  which  it  belongs. 
Such  a  comparison  shows  that  the  weights  of  the  seedling 
are  sometimes  above  and  sometimes  below  the  average 
weights. 

7.     Quintile  Distributions. 

An  article  by  Pearl  and  Surface  (14)  on  "Growth  and 
Variation  in  Maize"  states,  on  page  120,  "There  is,  then,  a 
marked  tendency  for  the  plants  which  were  relatively  small 
at  the  beginning  of  the  season  to  have  remained,  on  the 
average,  relatively  small  throughout  most  of  the  season." 
Or,  to  quote  further  (page  170),  "Extreme  variants  at  the 
beginning  of  the  season  tend  strongly,  on  the  whole,  to  re- 
main extreme  variants  during  the  whole  season."  This 
tendency  is  said  to  be  due  to  the  effect  of  internal  rather 
than  to  external  stimuli. 

Reed,  (15)  in  studying  growth  and  variability  in  Helian- 
thus,  follows  the  method  of  argument  of  Pearl  and  Surface 
and  concludes  that,  "Plants  which  started  in  a  given  quar- 
tile  showed  a  well-marked  tendency  to  remain  in  that  quar- 
tile  during  the  entire  grand  period  of  growth.  Plants  which 
were  small  at  maturity  were  generally  small  from  the  be- 
ginning, those  which  were  large  at  maturity  had  a  well- 
marked  superiority  from  the  start."  He,  too,  thinks  plants 
show  this  tendency  because  of  inherent  factors. 

In  order  to  determine  whether  the  seedlings  used  in  the 
present  experiments  revealed  similar  traits  the  data  for  all 
seedlings  which  were  grown  in  water  and  which  were 
placed  in  the  25° C  temperature  case  on  the  sixth  day  after 
placing  them  to  germinate,  were  collected.  A  group  of 
75  seedlings  containing  individuals  from  seeds  of  all  den- 
sities and  sizes  was  thus  obtained.  The  heights  of  these 
seedlings  on  each  successive  day  and  the  density  and  size 
of  the  seeds  from  which  each  grew  are  given  in  *  Table  49. 

*It  has  been  found  necessary  in  the  publication  of  these  experiments  to  omit 
Tables  1-17,  21-36,  40-49.  These  tables  can  be  found  in  the  original  thesis  at  the 
Library  of  the  University  of  Illinois. 


20 

The  seedlings  are  arranged  and  numbered  according  to 
their  size  on  the  first  day,  that  is,  on  the  day  they  were 
placed  in  the  constant  temperature  case  and  six  days  after 
planting.  Following  the  method  given  in  the  articles  cited, 
these  75  seedlings  are  arranged  in  five  groups,  or  quintiles, 
according  to  their  size  on  the  first  day.  In  order  to  avoid 
having  seedlings  of  the  same  size  fall  in  two  different  quin- 
tiles, the  number  of  plants  in  the  quintiles  varies.  Thus, 
Quintile  I  contains  the  15  smallest  seedlings  on  each  day 
of  measurement.  Quintile  II  contains  the  16  next  larger; 
Quintile  III,  the  17  next  larger;  Quintile  IV,  the  12  next; 
and  Quintile  V,  the  15  largest  ones.  The  number  of  seed- 
lings in  the  respective  quintiles  was  maintained  during 
the  growth  period.  In  but  two  cases,  after  the  initial  dis- 
tribution, did  two  seedlings  fall  on  the  separating  line  of 
contiguous  quintiles.  In  these  cases  one  of  the  seedlings 
was  arbitrarily  placed  in  the  next  highest  quintile.  The 
quintile  distribution  for  each  successive  day  for  seedlings 
starting  in  the  several  quintiles  is  given  in  Tables  50  to 
54.  These  tables  give  the  total  number  of  distributions, 
excluding  those  of  the  first  day,  when,  of  course,  all  distri- 
butions were  in  the  particular  quintile  to  which  the  seed- 
lings were  originally  assigned,  and  also  the  mean  quintile 
position  for  each  day.  A  study  of  the  tables  shows  that  by 
the  sixth  day  only  3  of  the  15  seedlings  which  started  in 
Quintile  I  are  still  in  this  quintile  and  by  the  tenth  day  only 
2  remain.  Three  of  the  15  reach  Quintile  V  by  the  ninth 
day.  Out  of  the  total  of  165  distributions  only  42,  or  25.5% 
are  in  Quintile  I.  The  mean  quintile  position  for  these 
seedlings  changes  from  1  on  the  initial  day  to  3  on  the 
eleventh  and  twelfth  days.  This  final  mean  quintile  posi- 
tion is  above  the  general  mean,  which  owing  to  the  differ- 
ence in  the  number  of  seedlings  in  the  several  quintiles  is 
2.95.  Only  18.8%  of  the  total  number  of  distributions  for 
seedlings  starting  in  Quintile  II  fall  in  this  quintile.  For 
Quintile  III  the  per  cent  is  20.9 ;  for  Quintile  IV,  it  is  25 ; 
and  for  Quintile  V,  25.5.  The  mean  quintile  position  for 
seedlings  starting  in  Quintile  V  drops  from  5  on  the  first 
day  to  2.87  on  the  ninth  day.  The  curves  for  the  mean 
quintile  positions  on  the  successive  days  are  plotted  in  Plate 
V.  As  is  to  be  expected  where  the  variation  can  be  in  either 


21 

of  two  directions,  there  is  a  smaller  shifting  of  the  mean 
quintile  positions  in  the  intermediate  quintiles  than  in 
Quintiles  I  and  V.  From  the  preceding  facts  it  appears 
that  seedlings  which  are  small  at  first  frequently  surpass 
in  growth,  larger  ones  of  equal  age. 

Let  us  consider  now  the  specific  gravity  and  the  size  of 
the  seeds  from  which  these  75  seedlings  grew.  Of  the  15 
seedlings  which  started  as  the  smallest,  Quintile  I,  (Table 
50),  7  are  from  small  seeds,  1  from  a  medium  and  7  from 
large  seeds.  The  2  seedlings  which  remain  in  Quintile  I  on 
the  last  day  are  from  small  seeds,  the  4  in  Quintile  II  are 
likewise  from  small  seeds.  The  seventh  seedling  from  small 
seeds  which  started  in  Quintile  I  is  from  a  seed  of  Density 
3  and  is  the  smallest  seedling  of  Quintile  III.  Of  the  3 
seedlings  which,  starting  in  Quintile  I,  reach  Quintile  V,  all 
are  from  large  seeds;  the  2  largest  in  this  case,  are  from 
seeds  of  Density  3,  the  third  from  a  seed  of  Density  5.  The  2 
seedlings  in  Quintile  IV  are  also  from  large  seeds.  The  seed- 
ling from  the  medium  seeds  is  in  Quintile  III.  Of  the  16 
seedlings  which  start  in  Quintile  II  (Table  51),  10  are 
from  small,  5  from  medium  and  1  from  large  seeds.  The 
6  seedlings  which  fall  back  into  Quintile  I  are  all  from 
small  seeds.  The  1  which  reaches  Quintile  IV  is  from  a 
large  seed.  In  Quintile  III,  (Table  52),  7  of  the  original 
17  are  from  small,  8  are  from  medium  and  2  from  large 
seeds.  The  3  seedlings  which,  starting  in  Quintile  III  re- 
cede to  Quintile  I,  are  from  small  seeds.  The  4  ending  in 
Quintile  II  are  also  from  small  seeds.  Of  the  5  which  end 
in  Quintile  V,  1  is  from  a  large  seed,  the  other  4  from  med- 
ium seeds.  The  second  seedling  from  large  seeds  starting 
in  Quintile  III  falls  just  below  Quintile  V.  All  of  the  seed- 
lings which  start  in  Quintile  IV  (Table  53)  are  from  med- 
ium seeds.  Of  the  5  which  reach  Quintile  V,  2  are  from 
seeds  of  Density  1  and  3  from  those  of  Density  3.  Ten  of 
the  15  seedlings  which  start  in  Quintile  V,  (Table  54),  are 
from  medium  seeds,  the  other  5  are  from  small  seeds.  On 
the  last  day,  3  of  those  from  small  seeds  are  the  seedlings 
in  Quintile  I,  the  other  2  are  in  Quintile  II.  Of  those  which 
remain  in  Quintile  V,  1  is  from  a  medium  seed  of  Density 
1,  the  other  is  from  a  medium  seed  of  Density  3. 


22 

Out  of  the  75  seedlings  in  the  group  in  question,  29  are 
from  small,  36  from  medium  and  10  from  large  seeds.  Of 
the  29  seedlings  from  small  seeds,  regardless  of  their  posi- 
tion on  the  first  day,  14  are  in  Quintile  I,  14  are  in  Quintile 
II  and  1  is  in  Quintile  III  on  the  last  day.  The  final  distri- 
bution of  the  seedlings  from  the  large  seeds  is  4  in  Quin- 
tile V,  4  in  Quintile  IV  and  2  in  Quintile  III.  From  the 
foregoing  statements  the  following  conclusions  seem 
justified: 

(1)  Seedlings  which  are  small  at  first  frequently  sur- 
pass in  growth,  larger  ones  of  equal  age; 

(2)  The  size  and  specific  gravity  of  the  seeds,  chiefly 
the  former,   are  more   definitely  correlated  with  growth 
than  is  the  initial  height  of  seedlings  of  the  same  age. 

SUMMARY 

Common  garden  bean  seed  was  separated  into  6  groups 
of  different  densities  by  the  use  of  sodium  nitrate  of  1.32, 
1.27,  1.22,  1.17,  and  1.12  specific  gravity.  The  seeds  of  each 
of  the  densities  were  then  grouped  according  to  length  into 
small,  medium  and  large. 

Seedlings  from  seeds  of  each  size  and  density  were  grown 
in  the  dark  at  25° C.  Seedlings  from  small  and  medium 
seeds  of  each  density  were  also  grown  in  the  dark  at  20° 
and  30°. 

Daily  measurements  were  taken  and  from  this  data  the 
daily  growth  increments  were  determined.  When  growth 
ceased  both  the  fresh  and  the  dry  weight  of  the  seedling 
was  obtained. 

A  study  of  the  results  made  evident  that: 

(1)  Seedlings  grown  from  seeds   of  1.32,   1.27,   1.22, 
1.17,   1.12   and   1.12- specific  gravity  differ  in  amount  and 
rate  of  growth. 

(2)  The  greatest  height  and  diameter  of  shoot,  also  the 
greatest  dry  weight,  for  seedlings  from  seeds  of  uniform, 
size  is  found  in  those  grown  from  seeds  of  1.22,  1.27  and 
1.32  specific  gravity,  seeds  of  1.22  or  1.27  usually  ranking 
first. 


23 

(3)  The  greatest  fresh  weight  is,  in  general,  found  in 
seedlings  grown  from  seeds  of  1.32,  1.27  and  1.22  specific 
gravity. 

(4)  The  lower  and  specific  gravity  of  the  seed,  the 
shorter  the  second  and  third  internodes  of  the  seedlings 
from  seeds  of  equal  size. 

(5)  The  greatest  rate  of  growth,  for  seedlings  from 
seeds  of  uniform  size,  is  usually  found  in  seedlings  from 
seeds  of  1.32,  1.27  or  1.22  specific  gravity. 

(6)  From  the  total  dry  weight  it  may  be  inferred  thai 
at  25  °C  the  seedlings  from  seeds  of  Density  6  use  their  re- 
served material  to  the  best  advantage. 

(7)  Seedlings  grown  from  small,   medium   and  large 
seeds  differ  in  amount  and  rate  of  growth. 

(8)  The  total  amount  of  growth  varies  directly  with 
the  length  of  the  seed. 

(9)  Size  and  weight  of  seedlings  from  seeds  of  uni- 
form specific  gravity  show  a  wider  variation  (more  espec- 
ially at  25° C)  between  those  from  small  and  medium  seeds 
than  between  the  ones  from  medium  and  large. 

(10)  Seedlings  from  seeds  of  medium  length  show  a 
greater  growth  rate  than  seedlings  from  either  small  or 
large  seeds  of  equal  specific  gravity. 

(11)  From  the  total  dry  weight  it  may  be  inferred  that, 
except  at  20 °C,  seedlings  from  the  large  and  medium  seeds 
use  their  reserve  material  to  better  advantage  than  those 
from  small  seeds. 

(12)  Seedlings  grown  in  water  contain  a  smaller  per 
cent  of  water  than  those  from  seeds  of  the  same  specific 
gravity  and  size  grown  in  soil.    They  are  also  less  brittle. 

(13)  The  root  system  of  seedlings  grown   in  soil  is 
larger  than  that  of  seedlings  grown  in  water. 

(14)  The  growth  equation  of  Blackman  does  not  apply 
to  seedlings  grown  in  the  dark. 

(15)  A  difference  in  level  in  the  insertion  of  the  coty- 
ledons on  the  axis  is  not  correlated  with  the  fresh  and  dry 
weights  of  either  root,  shoot  or  plant. 


24 

(16)  Seedlings  which  are  small  at  first  frequently  sur- 
pass in  growth  larger  ones  of  equal  age. 

(17)  The  size  and  specific  gravity  of  the  seeds  are  more 
definitely  correlated  with  growth  than  is  the  initial  height 
of  seedlings  of  the  same  age. 


The  author  wishes  to  thank  Professor  Charles  F.  Hottes, 
not  only  for  suggesting  the  problem,  but  also  for  his  kindly 
criticisms  and  helpful  suggestions  during  the  progress  of 
the  work. 

BIBLIOGRAPHY 

1.  Blackman,  V.  H. :     The  Compound  Interest  Law  and  Pknt  Growth. 

(Annals  of  Botany,  33:353-360,  1919.) 

2.  Clark,    V.     A. :       Seed     Selection    According    to     Specific     Gravity, 

(N.  Y.  Agri.  Exp.  Sta.  Bull.  256,  1904.) 

3.  Degrully,  L. :     Selection  des  bles  et  autres  semences  par  la  densite. 

(Le  Progres  Agricole  &  Viticole,  30:453-455,  1898.) 

4.  Deherain,  P.  P.  et  Dupont,  C. :     Culture  du  ble  au  champ  d'exper- 

iences  de  Grignon,  en  1902.  (Compt.  Rend,  de  1'Acad.  des  Sci., 
135:654-657,  1902.) 

5.  DeVries,  H. :     The  Mutation  Theory,  Vol.  I,  (1909). 

6.  Haberlandt,  F. :      Ueber  den  Einfluss  das  Samens  auf  den  Ernteer- 

trag.  (Bohimisches  Centralblatt  fur  die  gesammte  Landeskultur. 
1866:4,  Abst.  in  Hoffmann  Jahresbereicht  Agr.  Chem.,  9:298-300, 
1868.) 

7.  Harris,  J.  A.:     Further  Studies  on  the  Interrelationship  of  Morpho- 

logical and  Physiological  Characters  in  Seedlings  of  Phaseolus. 
(Brooklyn  Bot.  Gard.,  Memoirs  1:167-174,  1918.) 

8.  111.   State  Water  Survey:     Analysis  of  the  Mineral  Content  of  Tap 

Water  of  the  University  of  111.     (Lab.  No.  30486,  1915.) 

9.  Johannsen,    W. :      Elemente  der  Exakten  Erblichkeitslehre.      Zweite 

Auflage.     (1913.) 

10.  Kiesselbach,  T.  A.,  and  Helm,  C.  A.  :     Relation  of  Size  of  Seed  and 

Sprout  Value  to  the  Yield  of  Small  Grain  Crop.  (Neb.  Agr.  Exp. 
Sta.  Res.  Bull.  11,  1917.) 

11.  Leighty,     C.    E. :      Correlation     of    Characters    in    Oats.       (Amer. 

Breeders'  Ass.  Rpt.  7  &  8:  50-61,  1911  &  1912.) 

12.  Love,  H.    Hi :     A    Study  of  the  Large  and    Small   Grain   Question, 

(Amer.  Breeders'  Ass.  Rpt.  7  &  8:109-118,  1911  &  1912.) 

13.  Meyers,  C.  H. :    Effect  of  Fertility  Upon  Variation  and  Correlation  in 

Wheat.     (Amer.  Breeders'  Ass.  Rpt.  7  and  8;  61-74,  1911,  1912.) 

14.  Pearl   R.,  and    Surface,   F.    M.  :      Growth   and  Variation  in    Maize, 

(Zeit.  Indukt.  Abstammungs  and  Vererbungslehre,  14:97-203,  1915.) 

15.  Reed,    H.    S.:      Growth    and    Variability   in    Helianthus.      (Amer.    Jour. 

Bot.  6:252-271,  1919.) 

16.  Sanborn,  J.  W. :       Selection  of    Seed.       (Utah  Agr.  Exp.  Sta.    Rpt. 

1892:133-137.) 

17.  Woolny,    E. :        Untersuchungen    ueber    die    Werthbestimmung    der 

Samen  als  Saat  und  Handelswaare.  (Jour,  fur  Landwirthschaft, 
25:75-116,  133-169,  1877.) 


25 


Series  A 

TABLE  18. 

WATER  CULTURE                                SMALL  SEEDS 
Temperature  25°  C 

Den-                     Average  Daily  Growth  Increments  in  Centimeters 

sity 

IH          1         2 

3456789         10       11        TH 

HYPOCOTYL 

1 

1.83    1.62     3.90 

3.30       .43       .01                                                                        II-09 

2 

1.85     4.05     4.47 

1.53       .21                                                                                   12.11 

3 

1.29     3.59     4.12 

1.45       .20                                                                                      1°-65 

4 

1.47    2.03     4.73 

2.38       .30       .04                                                                        10.95 

5 

1.50     2.17     4.17 

2.56       .71       .11                                                                           11-23 

6 

1.25     3.07     5.23 

2.27       .33       .02                                                                           12.17 

FIRST  INTERNODE 

1 

.26       .47 

1.63    3.45    3.13       .59       .45       .16       .01                           11.15 

2 

.40       .77 

1.84    3.68     2.94       .56       .56       .19       .01                            11.95 

3 

.36       .75 

2.34     3.60    2.86       .29       .40       .15                                        11.75 

4 

.28       .50 

1.54     3.96     3.11       .66       .53       .25       .01                            11.84 

5 

.24       .36 

1.13     2.81     2.90       .84       .70       .10       .03                            10.11 

6 

.27       .59 

1.58     3.30     2.63       .32       .50       .13       .07                            10.37 

SECOND  INTERNODE 

1 

.04       .10       .16       .21       .41       .35       .25       .08       .05      1.65 

2 

.04       .15       .05       .13       .20       .29       .07       .01                    .94 

3 

.10       .15       .06       .17       .30       .20       .08       .03       .01      1.10 

4 

.08       .10       .09       .10       .16       .18       .18       .02                    .91 

5 

.03       .10       .13       .08       .16       .17       .19       .13       .03      1.01 

6 

.10       .15       .02       .08       .08       .05                                .48 

THIRD  INTERNODE 

1 

.01       .01       .05       .01                                .08 

2 

.01       .03       .03                                .06 

3 

.01       .03       .01                              .01         .06 

4 

.01       .04       .01                     .06 

5 

.01       .03                               .04 

6 

.02                                            .02 

SHOOT 

1 

1.83    1.89    4.37 

4.96     3.98     3.30     1.81       .88       .56       .27       .07       .05     23.97 

2 

1.85     4.45     5.25 

3.40     4.04     2.99     1.69       .77       .50       .11       .01                25.06 

3 

1.29     3  95     4  87 

3  88     3.95     2.93     1.47       .72       .36       .08       .03       .03     23.56 

4 

1.47     2.30     5.24 

3.99     4.36     3.24    1.76       .69       .45       .24       .04                23.78 

5 

1.50    2.41     4.52 

3.71    3.63    3.14    1.93       .86       .29       .24       .13       .03    22.40 

6 

1.25     3.33    5.80 

3.85    3.74    2.80    1.34       .58       .23       .08                           23.00 

Average 

Av- 

Wt.  &  Length 

Average  Fresh                     Average  Dry  Weight      erage 

(gram)     (mm) 

Weight  in  grams  of                      In  grams  of            Diam. 

of  Seed 

Root      Shoot      Plant              Root      Shoot      Plant    (mm) 

1 

.2666        10.7 

.3269        1.3800        1.7069         .0170         .1010         .1180        2.6 

2 

.2581        10.8 

.3318        1.3084        1.6402         .0184         .0941         .1125         2.7 

3 

.2757        10.8 

.3648        1.3596        1.7244         .0196         .0992         .1188        2.7 

4 

.2526        10.4 

.3197        1.2845        1.6042         .0164         .0931         .1095        2.6 

5 

.2227        10.5 

.3024        1.1356        1.4380         .0157         .0839         .0996        2.5 

6 

.1713        10.1 

.2212           .9623        1.1835         .0124         .0657         .0781        2.3 

IH—  Height  when  placed  in  temperature  case.    TH—  Total  height. 

26 


TABLE  19. 

Series  B  WATER  CULTURE  MEDIUM  SEEDS 

Temperature   25  °C 

Den-  Average  Daily  Growth  Increments  in  Centimeters 

sity  IH..    1          2          3          4         5          6          7          89          10      11      12      TH 

HYPOCOTYL 


1 

2 
3 

4 
5 
6 

i 

2 
3 
4 
5 

C 

1.94     4.32 
2.25     4.60 
1.84    5.50 
1.86     4.21 
1.43     2.10 
1.84    3.27 

.44 
.40 
.44 
.51 
.33 
.33 

5.35     1.84 
4.58     2.14 
6.33    1.34 
5.24       .94 
6.59     3.44 
6.17     3.06 

.84     2.99 
.66     2.29 
1.28     2.90 
1.10    3.74 
.51     1.81 
.57     1.81 

.10 
.07 
.05 
.09 
.87       ,01       .06 
.53       .11 

FIRST  INTERNODE 
4.17     2.52       .84       .16 
4.61     3.85     1.60       .51 
4.05     2.51       .94       .30 
3.85     1.53       .63       .25 
4.16     4.67     2.64       .97 
5.24     3.70     1.51       .63 

.15 
.06     .02 
.06 
.34     .06 
.24     .01 

.02 
.01 

13.55 
13.64 
15.05 
12.34 
14.47 
14.99 

11.96 
14.08 
12.50 
11.66 
15.51 
14.06 

SECOND  INTERNODE 

1 

15 

.31 

.91     2.36 

2.98     1 

.19     .41 

.10     . 

05 

8.46 

2 

06 

.18 

.21       .42 

1.24    1 

.53     .52 

.10 

4.26 

3 

.04       '. 

16 

.20 

.66     2.23 

1.84    1 

.14     .42 

.06     . 

01 

6.76 

4 

.18       . 

14 

.16 

.84       .98 

.73 

.36     .21 

.05 

3.64 

5 

• 

01 

.04 

.20       .23 

.40 

.57     .36 

.23     . 

16 

2.20 

C 

01 

.09 

.24       .40 

.47 

.54     .49 

.24     . 

07 

.06 

2.61 

THIRD  INTERNODE 

1 

.15 

.25 

.15     .14 

.10     . 

05 

.84 

2 

.04 

.16     .08 

.28 

3 

.11 

.15 

.16     .18 

.08     .05 

.73 

4 

.05 

.08     .05 

.03 

.20 

5 

.04 

.01     . 

04 

.10 

6 

.03 

.01     .04 

.03     . 

01 

.01 

.14 

FOURTH  INTERNODE 

3 

.05 

.01 

.06 

SHOOT 

1 

1.94    4.76 

6.19    4 

.97 

4.59 

3.44     3.35 

3.39    1 

.34     .55 

.20     .10 

34.81 

2 

2.25     5.00 

5.34    4 

.49 

4.86 

4.06     2.02 

1.79     1 

.84     .60 

.10 

32.25 

3 

1.84    5.94 

7.63     4 

.40 

4.30 

3.18     3.28 

2.29     1 

.36     .67 

.15     .06 

35.10 

4 

1.86     4.73 

6.33     4 

.85 

4.08 

1.69     1.46 

1.27 

.86     .41 

.24     .05 

27.83 

5 

1.43     2.43 

7.10    5 

.27 

5.07 

4.89     2.90 

1.37 

.91     .46 

.26     . 

20 

32.29 

6 

1.84     3.60 

6.74    4 

.89 

5.86 

4.06     1.91 

1.13 

.80     .54 

.27     .09 

.07 

31.80 

Average 

Av- 

Wt. & 

Length 

Average  Fresh 

Average  Dry  Weight 

erage 

(gram)     (mm) 

Weight  in  grams 

of 

In 

grams 

of 

Diam. 

of 

Seed 

Root 

Shoot      Plant 

Root 

Shoot 

Plant 

(mm) 

1 

.4407 

13.7 

3495 

2.1925         2.5420 

.0239 

.1715 

.1954 

3.1 

2 

.3851 

12.9 

3240 

1.8985         2.2225 

.0199 

.1492 

.1691 

2.9 

3 

.3915 

13.5 

.3002 

2.0435        2.3437 

.0197 

.1519 

.1716 

3.0 

4 

.3134 

13.1 

t 

3501 

1.6348        1.9849 

.0191 

.1164 

.1355 

2.8 

5 

.3290 

13.1 

3259 

1.6671        1.9930 

.0195 

.1216 

.1411 

2.9 

6 

.2915 

13.3 

3139 

1.5851         1.8990 

.0169 

.1148 

.1317 

2.7 

27 


TABLE  20 

Series   C  WATER  CULTURE  LARGE  SEEDS 

Temperature   25  °C 


Den- 

Average Daily  Growth  Increments  in  Centimeters 

sity 

IH       1 

2 

3 

4 

5          6 

7 

8        9 

10 

11       12 

TH 

HYPOCOTYL 

1    1. 

80    2.40 

5.65 

2.25 

.05 

12.15 

2     1. 

87     2.93 

5.13 

2.33 

.10 

12.37 

3    1. 

13     1.37 

3.47 

3.97 

2.33 

.22 

12.48 

4     1. 

10    2.05 

4.92 

4.33 

1.08 

.10 

13.58 

5     1. 

70     3.00 

4.40 

3.63 

.83 

13.55 

FIRST  INTERNODE 

1 

.40 

1.15 

4.35 

4.15 

2.25       .70 

.15 

13.15 

2 

.43 

.85 

3.73 

4.25 

3.18       .62 

.12 

13.18 

3 

.30 

.33 

.72 

2.77 

4.95     3.22 

.97 

.28       .03 

13.57 

4 

.28 

.27 

1.23 

2.75 

4.47     3.17 

.80 

.15 

13.12 

5 

.30 

.35 

1.25 

3.00 

4.70    2.90 

.50 

.13 

13.13 

SECOND   INTERNODE 

1 

.25 

.30 

1.20 

3.70     2.70 

1.05 

.35       . 

15 

9.70 

2 

.30 

.45 

1.52     3.90 

2.38 

.68       . 

13 

9.37 

3 

.03 

.15 

.40     1.20 

2.67    2.13       . 

82 

.38 

.12 

7.90 

4 

.12 

.30       .65 

1.80    1 

.55       . 

58 

.42 

.18 

5.60 

5 

.08 

.37       .75 

1.38     1.30       . 

63 

.15 

.05     .02 

4.93 

THIRD  INTERNODE 

1 

.35       .15 

.25 

.20       . 

15 

.10 

.15     .10 

1.15 

2 

.12       .28 

.37 

.28       . 

08 

.03 

1.17 

3 

.12 

.18 

.18       . 

15 

.08 

.02 

.73 

4 

.12 

.12       . 

03 

.07 

.03 

.37 

5 

.10 

.15 

,08 

.10 

.02 

.45 

FOURTH  INTERNODE 

1 

.05 

.05 

SHOOT 

1     1 

.80     2.80 

6.80 

6.85 

4.50 

3.50    4.55 

3.10     1 

.25       , 

,50 

.25 

.15     .15 

36.20 

2     1 

.87     3.37 

5.98 

6.37 

4.80 

4.82    4.80 

2.87 

.97       , 

,18 

.07 

36.08 

3     1 

.13    1.66 

3.80 

4.71 

5.25 

5.56     4.57 

3.81     2 

.62     1, 

03 

.46 

.13 

34.73 

4    1 

.10    2.32 

5.20 

5.55 

3.95 

4.88     3.82 

2.73    1 

.82       , 

,(30 

.50 

.20 

32.68 

5     1 

.70     3.30 

4.75 

4.88 

3.90 

5.07     3.65 

2.18    1 

.57 

,70 

.25 

.10     .02 

32.07 

Average 
Wt.  &  Length 
(gram)     (mm) 
of  Seed 

Average  Fresh 
Weight  in  grams  of 
Root      Shoot      Plant 

Average  Dry  Weight 
In  grams  of 
Root      Shoot      Plant 

Av- 
erage 
Diam. 
(mm) 

1 

.4957 

16.2 

5499 

2.4527        3 

.0026 

.0295 

.1872 

.2167 

3.3 

2 

.5272 

16.1 

.6445 

2.5433        3 

.1878 

.0331 

.2059 

.2391 

3.5 

3 

.5174 

16.9 

3644 

2.6313        2 

.9957 

.0271 

.2099 

.2370 

3.5 

4 

.3966 

15.8 

3347 

2.1359        2 

.4706 

.0193 

.1629 

.1822 

3.1 

5 

.4147 

15.3 

. 

2699 

2.1988        2 

.4687 

.0189 

.1699 

.1888 

3.2 

28 


Series  D 


TABLE  37 

SOIL  CULTURE 


SMALL  SEEDS 
Temperature   25  °G 


Den- 

Average Daily  Growth  Increments  in  Centimeters 

sity 

IH 

1         2 

3 

4          5 

6 

7 

8 

9         10       11 

TH 

HYPOCOTYL 

1 

1.63    2.40    5.37 

5.08 

.26 

14.76 

2 

2.11    3.70    5.60       .98 

.04 

12.43 

3 

2.26    3.55    4.61 

1.74 

.10 

12.26 

4 

2.11    2.79    6.55 

2.75 

.14 

14.34 

5 

1.29    2.58    5.71 

4.13 

.37 

14.08 

6 

2.36    3.26    5.70 

1.89 

.06 

13.27 

FIRST  INTERNODE 

1 

.23       .53 

2.31 

3.94    1.77 

.51 

.14 

.03 

9.47 

2 

.45    1.38 

3.05 

2.58       .84 

.25 

.07 

8.62 

3 

.41    1.11 

2.59 

2.49    1.18 

.32 

.08 

.01 

8.19 

4 

.31       .91 

2.85 

3.29     1.14 

.21 

.08 

.01 

8.80 

5 

.24       .53 

1.56 

2.99     2.02 

.46 

.15 

7.95 

6 

.36       .76 

2.61 

2.94    1.06 

.17 

.03 

7.91 

SECOND  INTERNODE 

1 

.16 

.18       .26 

.57 

.49 

.21 

1.87 

2 

.11 

.17 

.14       .30 

.50 

.24 

.06 

.01 

1.54 

3 

.01 

.11 

.18       .14 

.18 

.16 

.05 

.01 

.84 

4 

.03 

.14 

.19       .21 

.35 

.16 

.06 

.01       .01 

1.16 

5 

.09 

.12       .09 

.05 

.10 

.01 

.01       .01 

.48 

6 

.11 

.16 

.16       .13 

.10 

.66 

THIRD  INTERNODE 

1 

.03 

.04 

.03 

.10 

2 

.04 

.04 

.01 

.01 

.10 

3 

.03 

.01 

.04 

4 

.01 

.04 

.01 

.06 

5 

.01 

.01 

6 

.03 

.03 

SHOOT 

1 

1.63    2 

.64    5.90 

7.56 

4.38     2.03 

1.11 

.67 

.27 

26.20 

2 

2.11    4 

.15    7.10 

4.20 

2.75    1.14 

.79 

.35 

.08 

.02 

22.69 

I 

2.26    3 

.96    5.74 

4.44 

2.76    1.31 

.53 

.25 

.06 

.01 

21.32 

4 

2.11    3 

.10    7.49 

5.74 

3.61     1.35 

.58 

.27 

.09 

.01       .01 

24.36 

5 

1.29    2 

.81    6.24 

5.77 

3.49     2.11 

.51 

.25 

.01 

.01       .01       .01 

22.51 

6 

2.36    3.61    6.46 

4.61 

3.14    1.21 

.30 

.16 

21.85 

Average 

Av- 

Wt. & 

Length 

Average  Fresh 

Average  Dry  Weight 

erage 

(gram) 

(mm) 

Weight  in  grams  of 

In 

grams  of 

Diam. 

of  Seed 

Root 

Shoot 

Plant 

Root 

Shoot      Plant 

(mm) 

1 

.2881 

11.0 

.3424 

1.6683 

2.0107 

.0200 

.1091         .1291 

2.8 

2 

.  2ooo 

10.7 

.3252 

1.5319 

1.8571 

.0219 

.0994         .1213 

2.8 

3 

.2444 

10.8 

.2609 

1.4573 

1.7182 

.0190 

.0907         .1097 

2.7 

4 

.2429 

10.5 

.2203 

1.4990 

1.7193 

.0163 

.0937        .1100 

2.5 

5 

.2164 

10.3 

.1504 

1.2380 

1.3884 

.0148 

.0801         .0949 

2.5 

6 

.1983 

10.8 

.1343 

1.1577 

1.2920 

.0157 

.0762         .0919 

2.4 

29 


Series  E 


TABLE  38 

SOIL  CULTURE 


MEDIUM  SEEDS 
Temperature   25  °C 


Den- 
sity     IH 

1         2.84    4 
2         2.67    4 
3         2.29    3 
4         2.54    3 
5         2.10    3 
6         3.14    5, 

Average  Daily  Growth  Increments  in  Centimeters 
12          34          5          6          78          9         10       11 

HYPOCOTYL 

.39    6.27    1.70 
.37    5.96    1.99       .27 
.53    8.11    4.07       .19 
.21     7.03     2.86       .15 
.21    8.03    3.67       .39       .04 
.04    6.48       .68       .04 

TH 

15.20 
15.26 
18.19 
15.79 
17.44 
15.38 

FIRST  INTERNODE 

1 

.41    1.31 

3.24 

2. 

91 

1.21 

.49 

.15 

9.73 

2 

.44     1.51 

3.23 

3 

.0(5 

.67 

.27 

.07 

9.26 

3 

.29       .79 

3.19 

3. 

88 

1.89 

.56 

.17 

.01 

10.78 

4 

.40     1.06 

3.40 

3. 

14 

1.13 

.42 

.15 

9.70 

5 

.33       .80 

2.74 

4. 

30 

2.27 

.40 

.11 

.03 

10.99 

6 

.62     1.54 

4.30 

3. 

12 

.92 

.26 

.06 

.04 

10.86 

SECOND  INTERNODE 

1 

.03 

.22 

29 

.85 

2.13     1 

.40 

.19 

.07 

5.18 

2 

.03 

.27 

. 

34 

.93 

1.46 

.86 

.26 

.01 

4.16 

3 

.20 

36 

.51 

1.11     1 

.03 

.31 

.19       .03 

3.74 

4 

.24 

23 

.32 

.84 

.60 

.20 

.01 

2.44 

5 

.13 

23 

.37 

.56 

.79 

.31 

.03       .01 

2.43 

6 

.04 

.18 

30 

.40 

.44 

.40 

.20 

.06 

2.02 

THIRD  INTERNODE 

1 

.13 

.18 

.01 

.01 

.33 

2 

.03 

.09 

.07 

.04 

.04 

.27 

3 

.06 

.09 

.07 

.21 

4 

.04 

.04 

.03 

.10 

5 

.04 

.01 

.01       .01 

.07 

6 

.02 

.02 

.04 

SHOOT 

1 

2.84    4 

.80     7.61 

5.16 

3. 

20 

2.06 

2.74    1 

.73 

.20 

.09 

30.43 

2 

2.67     4 

.81     7.50 

5.49 

3. 

G7 

1.63 

1.81     1 

.00 

.30 

.06 

28.94 

3 

2.29     3 

.81     8.90 

7.46 

4. 

43 

2.40 

1.68     1 

•  2§ 

.41 

.26       .02 

32.91 

4 

2.54     3 

.61     8.09 

6.46 

3. 

53 

1.44 

1.26 

.81 

.25 

.04 

28.03 

5 

2.10     3 

.54    8.83 

6.54 

4. 

91 

2.69 

.96 

.94 

.36 

.04       .03 

30.94 

6 

3.14    5 

.66    8.06 

5.16 

3. 

46 

1.32 

.70 

.46 

.36 

.08 

28.30 

Average 

Av- 

Wt. & 

Length 

Average  Fresh 

Average  Dry  Weight 

erage 

(gram) 

(mm) 

Weight 

in  grams  of 

In 

grams  of 

Diam. 

of 

Seed 

Root 

Shoot 

Plant 

Root 

Shoot      Plant 

(mm) 

1 

.4176 

13.3 

.4172 

2.3848 

2.8020 

.0294 

.1630         .1924 

3.3 

2 

.4215 

13.3 

.4485 

2.5520 

3.0005 

.0327 

.1659         .1986 

3.2 

3 

.3579 

13.3 

.3072 

2.4495 

2.7567 

.0228 

.1407         .1635 

3.1 

4 

.3354 

13.0 

.3574 

2.0892 

2.4466 

.0266 

.1293         .1559 

3.1 

5 

.3334 

13.2 

.2886 

2.0904 

2.3790 

.0235 

.1288         .1523 

3.0 

6 

.3072 

13.4 

.5046 

1 

.9502 

2.4548 

.0294 

.1206         .1500 

3.0 

30 


Series  F 


TABLE  39 

SOIL  CULTURE 


LARGE  SEEDS 
Temperature   25  °C 


Den- 

Average Daily  Growth  Increments  in  Centimeters 

sity 

IH 

1 

2 

3 

4 

5 

6 

7 

8 

9         10       11 

TH 

HYPOCOTYL 

2 

2.17     3.17     5.90 

2.07 

.11 

13.42 

3 

2.22    2 

.75    5.25 

3.60 

.27 

14.08 

4 

2.93    5.07     4.83 

.53 

13.36 

5 

2.53     3 

.33    i 

B.25 

2.60 

.18 

14.9ft 

FIRST  INTERNODE 

2 

.53 

1.67 

3.99 

3.53 

1.14 

.44 

.14 

.03 

.01 

11.48 

3 

.33 

.80 

2.65 

4.63 

2.50 

.67 

.15 

11.73 

4 

.63 

2.23 

3.63 

2.83 

1.03 

.23 

.13 

10.73 

5 

.38 

1.08 

3.35 

3.70 

1.32 

.18 

.07 

.02 

10.10 

SECOND   INTERNODE 

2 

.10 

.27 

.49 

1.39 

1.49 

.54 

.19 

.04 

4.50 

3 

.15 

.33 

.92 

2.33     1 

.  77 

.45 

.03 

5.98 

4 

.03 

.23 

.47 

.83 

.90 

.43 

.07 

2.97 

5 

.27 

.40 

.63 

1.12 

.43 

.20 

.01 

3.06 

THIRD  INTERNODE 

2 

.04 

.13 

.07 

.03 

.03 

,3ft 

3 

.05 

.10 

.15 

.07 

'.37 

4 

.03 

.07 

.03 

.07 

.20 

5 

.12 

.02 

.05 

.18 

SHOOT 

2 

2.17     3 

.70 

7.67 

6.33 

4.13 

2.57 

2.06 

.76 

.24 

.09 

29.71 

3 

2.22     3 

.08 

6.05 

6.40 

5.23 

3.47 

3.10     2 

.10 

.52 

.03 

32.17 

4 

2.93     5 

.70 

7.10 

4.40 

3.30 

1.90 

1.20 

.60 

.13 

27.27 

5 

2.53     3 

.72 

7.33 

6.22 

4.28 

1.95 

1.42 

.52 

.27 

28.25 

Average 

Av- 

Wt. & 

Length 

Average  Fresh 

Average 

Dry  Weight 

erage 

(gram)     (mm) 

Weight  in  grams  of 

In  grams  of 

Diam. 

of 

Seed 

Root      Shoot 

Plant 

Root 

Shoot      Plant 

(mm> 

2 

.4421 

15 

.6 

.2043 

2. 

4114 

2.6157 

.0287 

.1719         .2006 

3.4 

3 

.4658 

16 

.2 

.4839 

2. 

7125 

3.1964 

.0360 

.1904         .2264 

3.3 

4 

.4162 

15 

.7 

.6050 

2. 

5739 

3.1790 

.0310 

.1718         .2028 

3.3 

5 

.3887 

15 

.6 

.3402 

2. 

3250 

2.6652 

.0260 

.1585         .1845 

3.1 

The  cost  of  printing  necessitates  the  omission  of  the   data  from  which  the 
following  tables  are  derived: 

TABLE  50 

Quintile  Distribution  on   Successive  Days  for 
Seedlings    Starting   on   Quintile   I. 


Quintile 

II 

III 
IV 
V 

1 
15 
0 

0 
0 
0 

2 
8 
6 
1 
0 
0 

3 
8 
6 
0 
0 
1 

4 
5 
7 
2 
1 
0 

5 
4 

7 
4 
0 
0 

6 
3 
6 
4 
2 
0 

7 
2 
5 
5 
2 
1 

8 
3 
5 
3 
2 
2 

9 
3 
4 
3 
2 
3 

10 
2 
5 
3 
2 
3 

11        12        Total* 
22                42 
44                5» 
4          4                33 
22                15 
3          3                16 
Grand  Total    165 

Mean  Quintile  Position 

1.00  1.53  1.67  1.93  2.00  2.33  2.67  2.67  2.87    2.93    3.00    3.00 

TABLE  51 

Quintile  Distribution  on   Successive  Days  for 
Seedlings  Starting  on  Quintile  II. 


Quintile           1 
I           0 
II        16 
III         0 
IV        0 
V          0 

Mean  Quintile 
2.00 

2        3 
5        4 
3        4 

8        7 
0        1 
0        0 

Position 
2.19  2.31 

4 
7 
1 
7 
1 
0 

2.13 

5 
7 
1 
6 
1 
1 

2.25 

6 
6 
3 
4 
3 
0 

2.25 

7        8 
6         6 
3        2 
4         6 
3        2 
0         0 

2.25  2.25 

9 
6 
4 
4 
2 
0 

2.13 

10 
6 
4 
5 
1 
0 

2.06 

11        12        Total* 
6          6               65 
44               3£ 
55               61 
11               16, 
00                 1 
Grand  Total    176> 

2.06    2.06 

31 


TABLE  52 


Quintile   Distribution   on   Successive   Days 
Seedlings  Starting  on  Quintile  III. 


for 


Quintile 

1         2 

3         4 

5 

6 

7 

8 

9 

10 

11 

12 

Total* 

I 

0        2 

1         2 

3 

4 

3 

3 

3 

3 

3 

3 

30 

II 

0        5 

5        5 

4 

2 

4 

4 

3 

3 

4 

4 

43 

III 

17         7 

5         2 

1 

4 

3 

3 

4 

4 

3 

3 

39 

IV 

0         3 

5         5 

C 

1 

2 

2 

2 

2 

2 

2 

32 

V 

0         0 

1         3 

3 

G 

5 

5 

5 

5 

5 

5 

43 

Grand  Total  187 

Mean  Quintile  Position 

3.00  2.fi5  3.00  3.12 

3.12 

3.18 

3.12 

3.12 

3.18 

3.18 

3.12 

3.12 

TABLE  53 


Quintile 


Quintile  Distribution  on  Successive  Days   for 
Seedlings  Starting  on  Quintile  IV. 


ile            1         2        3 
I            001 
II            020 
III           013 
IV         12        4        1 
V            057 

Quintile  Position 
4.00  4.00  4.08 

4 
1 
0 
2 
3 
6 

4.09 

5 
1 
1 
2 
2 
0 

3.92 

6 
0 
2 
2 
2 
6 

4.00 

7 
2 
0 
1 
2 
7 

4.00 

8 
1 
1 
1 

9 
1 
1 
1 

10 
1 
1 
1 

11 
1 
1 
1 

12 
1 
1 
1 

Total* 
10 
10 
16 
33 
63 
tal    132 

6 
4.00 

5 
3.92 

5 
3.92 

5          5 
Grand  To 

3.92     3.92 

TABLE  54 


Quintile  Distribution  on  Successive  Days   for 
Seedlings  Starting  on  Quintile  V. 


Quintile            1        2        3 
I             000 
II            0        0        2 
III           002 
IV          0        5         5 
V         15       10        6 

Mean  Quintile  Position 
5.00  4.67  4.00 

4 
0 
3 
4 
2 
6 

3.73 

5 
0 
3 
4 
3 
5 

3.67 

6 
2 
3 
3 
4 
3 

3.20 

7 
2 
4 
4 
3 
2 

2.93 

8 
2 
4 
4 
3 
2 

2.93 

9 
2 
4 
5 
2 
2 

2.87 

10 
3 
3 
4 
3 
2 

2.87 

11         12        Total* 
33                17 
33                32 
44                38 
3          3                36 
22               42 
Grand  Total    165 

2.87    2.87 

*Total  distribution  exclusive  of  first  day. 


VITA 

The  author  received  her  secondary  education  at  her 
native  city,  Woodstock,  Illinois.  She  graduated  from  the 
Illinois  State  Normal  University  in  1902  after  which  she 
taught  High  School  Mathematics  and  Science  for  six  years. 
A  year  and  a  half  was  then  spent  teaching  under  the  Pres- 
byterian Mission  Board,  in  the  mountains  of  Tennessee. 
The  degree  of  A.  B.  was  received  from  the  University  of 
Illinois  in  1911,  and  that  of  A.  M.  from  the  same  Uni- 
versity in  1912.  Two  years  were  spent  as  Instructor  of 
Mathematics  and  Physics  at  Maryville  College,  and  one 
year  as  Assistant  Professor  of  Mathematics  at  Tusculum 
College.  Since  1916  she  has  been  an  Assistant  in  Botany  at 
the  University  of  Illinois,  assisting*  during  the  past  year 
and  a  half  chiefly  in  Plant  Physiology. 


'"aer 


4918 


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